CONTENTS. 



MICROSCOPIC DRAWING AND ENGRAVING. 



CHAP. I. 1. Beautiful precision of 

 the minute structure of natural 

 objects. 2. Cornea of a fly's eye. 

 3. Number of eyes of different in- 

 sects. 4. Astonishing precision of 

 artificial objects. 5. Demand for 

 such objects by Microscopists. 6. 

 Classes of such artificial objects. 

 7. Microscopic scales. 8. Method 

 of engraving them. 9. Measure- 

 ment of microscopic objects with 

 them. 10. Their minuteness. 11. 

 Scales of Mr. Froment. 12. Rect- 

 angular scales. 13. Micrometric 

 threads. 14. Necessity for micro- 

 scopic tests. 15. Test-objects. 

 16. Telescopic tests ; double stars. 

 17. Nebulae and stellar-clusters. 

 18. Effects of different telescopes 

 upon them : telescopes of Herschel 

 and Lord Rosse. 19. Remarkable 

 nebulae described by Herschel. 20. 

 Differently seen by Lord Rosse. 

 21. Microscopic tests. 22. Im- 

 proved powers of microscope. 23. 

 The Lepisma-Saccharina. 24. The 

 Podura, or Spring-tail. 



CHAP. II. 25. Natural tests not in- 

 variable. 26. Natural tests im- 

 perfect standards. 27. Nobert's 

 test-plates. 28. The degree of 

 closeness of their lines. 29. Their 

 use. 30. Apparent error respecting 

 them. 31. Froment' s microscopic 

 engraving. 32. Method of executing 

 it. 33. Various methods of micro- 

 scopic drawing. 34. Drawings by 

 squares. 35. Dr. Goring's drawings. 

 36. Structure and metamorphosis 

 of insects. 37. The day-fly. 38. 

 The larva of this insect. 39. Its 

 organs of respiration. 40. Its gene- 

 ral structure. 41. Its mobility. 

 42. State of chrysalis. 43. The 

 perfect insect. 44. The production 

 and deposition of its eggs, and its 

 death. 45. Death may be delayed 

 by postponing the laying of the eggs. 

 46. They take no food. 47. Their 

 countless numbers ; their bodies 

 used as manure. 



CHAP. III. 48. The beetle. 49. Its 

 larva, 50. Drawing of it in its 



natural size. 51. Dr. Goring's 

 magnified drawing. 52. Production 

 of the beetle from the egg. 53. The 

 young larva. 54. Its voracity and 

 manner of seizing its prey. 55. 

 Description of its organs. 56. Its 

 chrysalis. 57. "Water-beetle. 58. 

 Gnat. 59. Dr. Goring's method of 

 drawing. 60. Drawing by the ca- 

 mera-lucida. 61. Section of the 

 human skin ; sweating-gland and 

 duct. 62. The itch insect. 63. 

 Method of obtaining it. 

 CHAP. IV. 64. Structure of the itch 

 insect. 65. Its habits. 66. The 

 mange insect. 67. Its form and 

 structure. 68. Defects incidental 

 to drawing with the camera. 69. 

 Microscopic photographs. 70. Mi- 

 croscopic daguerreotypes by Messrs. 

 Donne and Foucault. 71. Descrip- 

 tion of the blood. 72. Red and 

 white corpuscles. 73. Daguerreo- 

 type of a drop of blood magnified. 



74. Magnitude of the corpuscles. 



75. Cause of the redness of blood. 



76. Corpuscles of inferior animals. 

 77. White globules. 78. White 

 grains. 79. White globules con- 

 verted into led corpuscles. 80. 

 Red corpuscles dissolved. 81. Cir- 

 culation of the blood. 82. Method 

 of showing it in the tongue of a frog. 

 83. The arteries distinguishable 

 from the veins. 84. The vascular 

 system of the tongue. 85. Mucous 

 glands. 86. Milk ; its constitution. 

 87. Magnified view of a drop of 

 milk. 88. The butter globules. 

 89. Their number variable. 90. 

 Analysis of the milk of different 

 animals. 91. Richness of woman's 

 milk. 92. Analogy of milk to 

 blood. 93. Importance 6f the qua- 

 lity of milk. 94. Its richness as- 

 certained. 95. Quevenne's hydro- 

 meter applied to milk. 96. Its 

 fallacy. 97. Donne's lactoscope. 

 98. Objections to it answered. 99. 

 Frauds practised by milk vendors. 

 100. Fore-milk and after-milk. 

 101. Self-engraved photographic 

 pictures. 



